package com.company.netsdk.audiopair;

public class CRCHelper {
	 final  long   crc32_table[]   =
		{
		    0x00000000,   0x77073096,   0xee0e612c,   0x990951ba,   0x076dc419,
		    0x706af48f,   0xe963a535,   0x9e6495a3,   0x0edb8832,   0x79dcb8a4,
		    0xe0d5e91e,   0x97d2d988,   0x09b64c2b,   0x7eb17cbd,   0xe7b82d07,
		    0x90bf1d91,   0x1db71064,   0x6ab020f2,   0xf3b97148,   0x84be41de,
		    0x1adad47d,   0x6ddde4eb,   0xf4d4b551,   0x83d385c7,   0x136c9856,
		    0x646ba8c0,   0xfd62f97a,   0x8a65c9ec,   0x14015c4f,   0x63066cd9,
		    0xfa0f3d63,   0x8d080df5,   0x3b6e20c8,   0x4c69105e,   0xd56041e4,
		    0xa2677172,   0x3c03e4d1,   0x4b04d447,   0xd20d85fd,   0xa50ab56b,
		    0x35b5a8fa,   0x42b2986c,   0xdbbbc9d6,   0xacbcf940,   0x32d86ce3,
		    0x45df5c75,   0xdcd60dcf,   0xabd13d59,   0x26d930ac,   0x51de003a,
		    0xc8d75180,   0xbfd06116,   0x21b4f4b5,   0x56b3c423,   0xcfba9599,
		    0xb8bda50f,   0x2802b89e,   0x5f058808,   0xc60cd9b2,   0xb10be924,
		    0x2f6f7c87,   0x58684c11,   0xc1611dab,   0xb6662d3d,   0x76dc4190,
		    0x01db7106,   0x98d220bc,   0xefd5102a,   0x71b18589,   0x06b6b51f,
		    0x9fbfe4a5,   0xe8b8d433,   0x7807c9a2,   0x0f00f934,   0x9609a88e,
		    0xe10e9818,   0x7f6a0dbb,   0x086d3d2d,   0x91646c97,   0xe6635c01,
		    0x6b6b51f4,   0x1c6c6162,   0x856530d8,   0xf262004e,   0x6c0695ed,
		    0x1b01a57b,   0x8208f4c1,   0xf50fc457,   0x65b0d9c6,   0x12b7e950,
		    0x8bbeb8ea,   0xfcb9887c,   0x62dd1ddf,   0x15da2d49,   0x8cd37cf3,
		    0xfbd44c65,   0x4db26158,   0x3ab551ce,   0xa3bc0074,   0xd4bb30e2,
		    0x4adfa541,   0x3dd895d7,   0xa4d1c46d,   0xd3d6f4fb,   0x4369e96a,
		    0x346ed9fc,   0xad678846,   0xda60b8d0,   0x44042d73,   0x33031de5,
		    0xaa0a4c5f,   0xdd0d7cc9,   0x5005713c,   0x270241aa,   0xbe0b1010,
		    0xc90c2086,   0x5768b525,   0x206f85b3,   0xb966d409,   0xce61e49f,
		    0x5edef90e,   0x29d9c998,   0xb0d09822,   0xc7d7a8b4,   0x59b33d17,
		    0x2eb40d81,   0xb7bd5c3b,   0xc0ba6cad,   0xedb88320,   0x9abfb3b6,
		    0x03b6e20c,   0x74b1d29a,   0xead54739,   0x9dd277af,   0x04db2615,
		    0x73dc1683,   0xe3630b12,   0x94643b84,   0x0d6d6a3e,   0x7a6a5aa8,
		    0xe40ecf0b,   0x9309ff9d,   0x0a00ae27,   0x7d079eb1,   0xf00f9344,
		    0x8708a3d2,   0x1e01f268,   0x6906c2fe,   0xf762575d,   0x806567cb,
		    0x196c3671,   0x6e6b06e7,   0xfed41b76,   0x89d32be0,   0x10da7a5a,
		    0x67dd4acc,   0xf9b9df6f,   0x8ebeeff9,   0x17b7be43,   0x60b08ed5,
		    0xd6d6a3e8,   0xa1d1937e,   0x38d8c2c4,   0x4fdff252,   0xd1bb67f1,
		    0xa6bc5767,   0x3fb506dd,   0x48b2364b,   0xd80d2bda,   0xaf0a1b4c,
		    0x36034af6,   0x41047a60,   0xdf60efc3,   0xa867df55,   0x316e8eef,
		    0x4669be79,   0xcb61b38c,   0xbc66831a,   0x256fd2a0,   0x5268e236,
		    0xcc0c7795,   0xbb0b4703,   0x220216b9,   0x5505262f,   0xc5ba3bbe,
		    0xb2bd0b28,   0x2bb45a92,   0x5cb36a04,   0xc2d7ffa7,   0xb5d0cf31,
		    0x2cd99e8b,   0x5bdeae1d,   0x9b64c2b0,   0xec63f226,   0x756aa39c,
		    0x026d930a,   0x9c0906a9,   0xeb0e363f,   0x72076785,   0x05005713,
		    0x95bf4a82,   0xe2b87a14,   0x7bb12bae,   0x0cb61b38,   0x92d28e9b,
		    0xe5d5be0d,   0x7cdcefb7,   0x0bdbdf21,   0x86d3d2d4,   0xf1d4e242,
		    0x68ddb3f8,   0x1fda836e,   0x81be16cd,   0xf6b9265b,   0x6fb077e1,
		    0x18b74777,   0x88085ae6,   0xff0f6a70,   0x66063bca,   0x11010b5c,
		    0x8f659eff,   0xf862ae69,   0x616bffd3,   0x166ccf45,   0xa00ae278,
		    0xd70dd2ee,   0x4e048354,   0x3903b3c2,   0xa7672661,   0xd06016f7,
		    0x4969474d,   0x3e6e77db,   0xaed16a4a,   0xd9d65adc,   0x40df0b66,
		    0x37d83bf0,   0xa9bcae53,   0xdebb9ec5,   0x47b2cf7f,   0x30b5ffe9,
		    0xbdbdf21c,   0xcabac28a,   0x53b39330,   0x24b4a3a6,   0xbad03605,
		    0xcdd70693,   0x54de5729,   0x23d967bf,   0xb3667a2e,   0xc4614ab8,
		    0x5d681b02,   0x2a6f2b94,   0xb40bbe37,   0xc30c8ea1,   0x5a05df1b,
		    0x2d02ef8d
		};

		public long crc32_byte(long crc, byte data)
		{
			return ((crc >> 8) & 0x00FFFFFF) ^ crc32_table[(int)((crc ^ data) & 0xFF)];
		}

		public long crc32(byte[] buffer, long length){
			long crc;
			int i;

			crc = 0xFFFFFFFF;
			for (i = 0; i < length; i++)
			{
				crc = crc32_byte(crc, buffer[i]);
			}
			return (crc ^ 0xFFFFFFFF);
		}

		public long crc32(long crc, byte[]  buffer, long length)
		{
			crc ^= 0xFFFFFFFF;
			int i = 0;
			while(length-- > 0)
			{
				crc = crc32_byte(crc, buffer[i++]);
			}
			return (crc ^ 0xFFFFFFFF);
		}
}
